add serialization to file code

5 files changed, 113 insertions, 35 deletions

diff --git a/client.c b/client.c
index c70e9d0..9a22d90 100644
--- a/client.c
+++ b/client.c
@@ -9,6 +9,7 @@
 #define TB_IMPL
 #include "termbox2.h"
 // clang-format on
+#include "common.h"
 #include "config.h"
 
 #include <arpa/inet.h>
@@ -32,10 +33,9 @@ int prompt_offs_y = 3;
 static int serverfd;
 // Input message to be send
 struct message input = {
-    .buf       = {0},
     .author    = USERNAME,
     .timestamp = {0},
-    .buf_len   = 0,
+    .len       = 0,
 };
 // All messages sent and received in order
 struct message *messages;
@@ -76,7 +76,7 @@ void screen_welcome()
     if (lines_available - nmessages < 0)
         skip = nmessages - lines_available;
     for (msg_y = skip; msg_y < nmessages; msg_y++) {
-        tb_printf(0, msg_y - skip, 0, 0, "%s [%s]: %s", messages[msg_y].timestamp, messages[msg_y].author, messages[msg_y].buf);
+        tb_printf(0, msg_y - skip, 0, 0, "%s [%s]: %s", messages[msg_y].timestamp, messages[msg_y].author, messages[msg_y].text);
     }
 }
 
@@ -84,10 +84,10 @@ void screen_welcome()
 void add_message(struct message msg)
 {
     int i;
-    for (i = 0; (messages[nmessages].buf[i] = msg.buf[i]); i++)
+    for (i = 0; (messages[nmessages].text[i] = msg.text[i]); i++)
         ;
-    messages[nmessages].buf[i]  = 0;
-    messages[nmessages].buf_len = i;
+    messages[nmessages].text[i] = 0;
+    messages[nmessages].len     = i;
     for (i = 0; (messages[nmessages].timestamp[i] = msg.timestamp[i]); i++)
         ;
     messages[nmessages].timestamp[i] = 0;
@@ -174,11 +174,11 @@ int main(void)
                     tb_print(global.cursor_x, global.cursor_y, 0, 0, " ");
                 }
                 tb_set_cursor(curs_offs_x, global.cursor_y);
-                input.buf_len = 0;
+                input.len = 0;
                 break;
             // send message
             case TB_KEY_CTRL_M:
-                if (input.buf_len <= 0)
+                if (input.len <= 0)
                     break;
                 while (global.cursor_x > curs_offs_x) {
                     global.cursor_x--;
@@ -187,7 +187,7 @@ int main(void)
                 tb_set_cursor(curs_offs_x, global.cursor_y);
 
                 // zero terminate
-                input.buf[input.buf_len] = 0;
+                input.text[input.len] = 0;
 
                 // print new message
                 time(&now);
@@ -200,7 +200,7 @@ int main(void)
                     err_exit("Error while sending message.");
 
                 // reset buffer
-                input.buf_len = 0;
+                input.len = 0;
 
                 // update the screen
                 // NOTE: kind of wasteful cause we should only display new message
@@ -211,28 +211,28 @@ int main(void)
             // remove word
             case TB_KEY_CTRL_W:
                 // Delete consecutive space
-                while (input.buf[input.buf_len - 1] == ' ' && global.cursor_x > curs_offs_x) {
+                while (input.text[input.len - 1] == ' ' && global.cursor_x > curs_offs_x) {
                     global.cursor_x--;
-                    input.buf_len--;
+                    input.len--;
                     tb_print(global.cursor_x, global.cursor_y, 0, 0, " ");
                 }
                 // Delete until next non-space
-                while (input.buf[input.buf_len - 1] != ' ' && global.cursor_x > curs_offs_x) {
+                while (input.text[input.len - 1] != ' ' && global.cursor_x > curs_offs_x) {
                     global.cursor_x--;
-                    input.buf_len--;
+                    input.len--;
                     tb_print(global.cursor_x, global.cursor_y, 0, 0, " ");
                 }
-                input.buf[input.buf_len] = 0;
+                input.text[input.len] = 0;
                 break;
             }
 
-            // append pressed character to input.buf
+            // append pressed character to input.text
             // TODO: wrap instead
-            if (ev.ch > 0 && input.buf_len < MSG_MAX && input.buf_len < global.width - 3 - 1) {
+            if (ev.ch > 0 && input.len < MSG_MAX && input.len < global.width - 3 - 1) {
                 tb_printf(global.cursor_x, global.cursor_y, 0, 0, "%c", ev.ch);
                 global.cursor_x++;
 
-                input.buf[input.buf_len++] = ev.ch;
+                input.text[input.len++] = ev.ch;
             }
 
         } else if (fds[FD_SERVER].revents & POLLIN) {
diff --git a/common.c b/common.c
index b177987..d72ead3 100644
--- a/common.c
+++ b/common.c
@@ -1,9 +1,12 @@
+#include "common.h"
 #include "config.h"
+
 #include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
 #include <strings.h>
 #include <unistd.h>
 
-// wrapper for write
 void writef(char *format, ...)
 {
     va_list args;
@@ -18,3 +21,57 @@ void writef(char *format, ...)
         n++;
     write(0, buf, n);
 }
+
+u16 str_len(char *str)
+{
+    u16 i = 0;
+    while (str[i])
+        i++;
+    return i;
+}
+
+void str_cpy(char *to, char *from)
+{
+    while ((*to++ = *from++))
+        ;
+}
+
+u8 save_message(struct message *msg, FILE *f)
+{
+    u8 err = 0;
+    u16 len;
+    if (msg->text == NULL) {
+        len       = 0;
+        msg->text = ""; // TODO: Error empty message should not be allowed.
+    } else {
+        len = str_len(msg->text);
+    }
+
+    if (len == 0)
+        err = 1;
+
+    fwrite(&msg->timestamp, sizeof(*msg->timestamp) * MSG_TIMESTAMP_LEN, 1, f);
+    fwrite(&msg->author, sizeof(*msg->author) * MSG_AUTHOR_LEN, 1, f);
+    fwrite(&len, sizeof(len), 1, f);
+    fputs(msg->text, f);
+
+    return err;
+}
+
+u8 load_message(struct message *msg, FILE *f)
+{
+    fread(msg, sizeof(*msg->timestamp) * MSG_TIMESTAMP_LEN + sizeof(*msg->author) * MSG_AUTHOR_LEN, 1, f);
+    u16 len;
+    fread(&len, sizeof(len), 1, f);
+    if (len == 0) {
+        // TODO: Error: empty message should not be allowed
+        // empty message
+        msg->text = "";
+        return 1;
+    }
+    char txt[len];
+    fgets(txt, len, f);
+    msg->text = txt;
+
+    return 0;
+}
diff --git a/common.h b/common.h
new file mode 100644
index 0000000..f737e2f
--- /dev/null
+++ b/common.h
@@ -0,0 +1,28 @@
+#include <stdint.h>
+#include <stdio.h>
+
+typedef uint8_t u8;
+typedef uint16_t u16;
+typedef uint32_t u32;
+
+// To serialize the text that could be arbitrary length the lenght is encoded after the author
+// string and before the text.
+struct message {
+    char timestamp[9]; // HH:MM:SS
+    char author[12];
+    u16 len;
+    char *text;
+};
+
+// printf without buffering using write syscall, works when using sockets
+void writef(char *format, ...);
+
+u16 str_len(char *str);
+void str_cpy(char *to, char *from);
+
+// save the message msg to file in binary format, returns zero on success, returns 1 if the msg.text
+// was empty which should not be allowed.
+u8 save_message(struct message *msg, FILE *f);
+// load the message msg from file f, returns zero on success, returns 1 if the msg.text
+// was empty which should not be allowed.
+u8 load_message(struct message *msg, FILE *f);
diff --git a/config.h b/config.h
index 039367d..626ccad 100644
--- a/config.h
+++ b/config.h
@@ -1,20 +1,11 @@
-#include <stdarg.h>
-#include <stdio.h>
-#include <unistd.h>
-
 #define PORT 9983
 // max size for a message sent
 #define BUF_MAX 255
 // max length of messages
 #define MSG_MAX 256
+// max length of author field
+#define MSG_AUTHOR_LEN 12
+// max length of timestamp field
+#define MSG_TIMESTAMP_LEN 9
 // current user's name
-#define USERNAME "unrtdqttr"
-
-void writef(char* format, ...);
-
-struct message {
-    char buf[MSG_MAX];
-    int buf_len;
-    char timestamp[9]; // HH:MM:SS
-    char author[12];
-};
+#define USERNAME "Jef Koek"
diff --git a/server.c b/server.c
index 63784d1..675bfb7 100644
--- a/server.c
+++ b/server.c
@@ -15,12 +15,14 @@
 // - max y for new messages and make them scroll
 // - check resize event
 // - asynchronously receive/send a message
+// - fix receiving messages with arbitrary text length
 
 // TODO: send message to all other clients
 // - implement different rooms
 // - implement history
 // - implement tls
 
+#include "common.h"
 #include "config.h"
 #include <arpa/inet.h>
 #include <errno.h>
@@ -33,6 +35,8 @@
 #define MAX_CONNECTIONS 5
 #define FD_MAX MAX_CONNECTIONS + 1
 
+static const char *filename = "history.dat";
+
 enum { FD_SERVER = 0 };
 int serverfd;
 
@@ -156,7 +160,6 @@ int main(void)
                     printf("Retransmitted message to client %d.\n", j);
             }
 
-
             // // TODO: check if bytes are correct
             // FILE *f = fopen("srv_recv.bin", "wb");
             // fwrite(&msg_recv, sizeof(struct message), 1, f);
@@ -164,7 +167,6 @@ int main(void)
             //
             // printf("written %lu bytes to srv_recv.bin\n", sizeof(msg_recv));
             // return 0;
-
         }
     }